The ROHS compliant parts are usually Matte Tin on the outer terminal plating.
There are also 2 further types of metal on the average chip cap - the undercoat metal of the outer electrode & the inner electrode. These are usually the same & are normally classed as base metal (usually copper) or precious metal (silver palladium).
Regarding reflow profiles, I've not heard of any problems, however a chip cap is not a demanding part to solder. Most manufacturers have suggested solder profiles on their websites.
I have access to a database with all Rohm, Kemet & Murata caps on, so if you have a specific question on any of these manufacturers I'll take a look.